 So in this video, I want to walk through an example of how we would carry out a bearing selection process. So the problem statement here is that we want to select an appropriate ball bearing that could be used to achieve continuous eight hours of operation per day at a rotating speed of 1800 rpm, and it's going to be expected to carry a radial load of 1.2 kilonewtons and a thrust load of 1.5 kilonewtons. We have to think a little bit about what assumptions we might make, some good assumptions that we could potentially make. We might stick with the 90% reliability requirement that's already built into the table in our in our book, and we might pick light impact as a possibility. So it's not not zero impact, but not heavy impact either as an option. So to go ahead and start solving this problem, we need to kind of figure some things out. Step one might be to find the equivalent loads. We can use it in our equations. Equivalent load first needs the ratio of thrust load to radial load. So we can divide that 1.5 by 1.2, and we get 1.25 as that ratio. That's greater than 0.35, so we need to go ahead and use the equation provided in order to to carry out that multiplication. So the equation provided is radial load times 1 plus 1.115 times thrust load over radial load, and doing that, carrying that out, we get an equivalent load of 2.4 kilonewtons. So this allows us to use that same set of equations, but now substituting in equivalent load. Next, we can choose an application factor and we can pull this from table 14.3 in the book. We said that we would assume light impact, so we're looking at that table, we have light impact, we're doing a ball bearing, gives a range, and we might select the the worst case scenario in order to account for everything in this case based on those assumptions. So we'll pick 1.5. Next, we need to choose our desired life. The book provides some suggestion in table 14.4, and based on our specifications that we have this eight hours of operation and whatever simplifying assumptions we can make, the book would suggest a life of 30,000 hours for this particular bearing. So from that, because life is going to be specified in in number of cycles, we can go ahead and calculate that based on our RPM. We'll multiply that times 30,000 hours times 60 minutes per hour, and from this we're going to get 3.24 times 10 to the ninth revolutions as our expected life of our bearing, or let's say desired life of our bearing. Next, we would want to pick our reliability factor. We already said that we're going to assume 90% reliability, and that gives us a reliability factor pulled from the book of one. So based on all of this information, the life that we've desired for our bearing and the other requirements, we can go ahead then and use one of our equations to calculate what the rated load capacity for our selected bearing should be in order to achieve this. So we have, just to reiterate the equation, fe, application factor, l over reliability factor, cr, excuse me, the 0.3. So we plug in what we have, remembering that this nine e to the seventh value is the rated life for the table that we have available from the book, and calculating this all out tells us that we have a rating rated load capacity requirement of 10 and a half kilonewtons. Great. So what can we go ahead and do with that? Well, now we take this number, remembering this number, 10.55 kilonewtons, and we go to table 14.2 in our book. Table 14.2 gives us three separate sets of data, radial ball bearing with an angle of zero degrees, angular ball bearing with an angle of 25 degrees and roller bearing. We're going with just radial ball bearing, and we'll use the the angle of zero degrees here. Now this gives different rated capacities under three different series of bearings. So an extra light, a light, and a medium series ball bearing. So we're going to go down this chart until we find something that meets our requirement. And the first one that goes above a rated capacity of 10 and a half kilonewtons is this 70 millimeter bore light, or extra light bearing. So an L00 70 millimeter. In my 200 column, the first one that goes above my rating is a 55 millimeter bore. Great. And in my 300 column, the first one that goes above my rating is a 35 millimeter bore. So we need to try to remember, now of course, I would write these down, but I can't have both screens up at the same time. We're going to remember 70, 55, and 35 millimeters for the three possible bearing options that we would choose. Now I'm going to go up here to table 14.1 and take a look at what that means for me. So if I come down here, my first one was a 70 millimeter. And that was in the light series. So that tells me that an L14 bearing would fit my my requirements. If I go for the next one, which was 55 millimeter bore in the 200 series, that would be a 211 bearing. And my last one was a 35 millimeter bore, which in the 300 series is a 307. So what that tells me is my possible bearing options for this are an L14, a 211, and a 307 series bearing. Now how we would then ultimately narrow down between those three options would be kind of whatever the rest of our requirements may be. Chances are that the requirement would come down to cost. So each of these are going to have a different cost associated with them. And possibly geometric constraints. So, you know, we're talking about a 35 millimeter bore diameter versus a 70 millimeter bore diameter from the 300 series to the L series. So that's, you know, very different size of bearing. So we might have geometric constraints that that therefore carry that out. So going back here, I would just make note of that I have three possible options based on this requirement, which is the in the L00 series, the 200 series, and the 300 series, my options were where my requirement came out as 70 millimeters, 55 millimeters, all bored, all of these are bore diameters and 35 millimeters, which led me to an L14, a 211, and a 307. And then somehow between my other possible requirements for the project, I would select among those three to be a potential solution to this problem. Thanks.